<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Hello jQuery</title>
    <script src="js/jquery-3.4.0.min.js"></script>
</head>
<body>
<script>
    $(document).ready(function () {
        alert("Hello jQuery!")
    })
</script>
</body>
</html>